The head of the munafiqoon who led the slander against Aisha and took away a third of the men in the battle of Uhud. Abdullah ibn Ubay, additionally referred to as ibn Salul in relevance his mother, was a chief of the Arab tribe Banu Khazraj and one amongst the leading men of Medina. He was a chief of the Arab tribe Banu Khazraj and one amongst the leading men of Medina (then called Yathrib). Upon the arrival of Muhammad, Ibn Ubayy became a Muslim, although the sincerity of that conversion is controversial.
Owing to perennial conflicts with Muhammad, Muslim tradition has labeled him a Munafiq (hypocrite) and "leader of the Munafiqun". Ibn Ubayy died 2 months when Muhammad came back, in 631. Despite the varied conflicts between the 2 men, Muhammad didn't show signs of vengefulness towards Ibn Ubayy, once he attended his observance and prayed on top of his grave.